Tensile stress control - esp non-contact detection of local stress differences in continuous widths of sheet material,eg

摘要

Non-contact detection of the tensile stresses in continuous widths of sheet materials which are more or less impermeable to air, is effected with an appts. which incorporates two spaced guide rollers as well as a device for producing an air or gas cushion between the appts. and the width of material. Pocket-like depressions on the side of the material web turned towards the air conduit are positioned w.r.t. each other in such a manner that they do not have any common partitions sepg. them as independent elements. The arrangement is such that the sum of the projected lengths of the pocket-like depressions on any longitudinal section in the sectional plane is pref. constant.